PROTOZOA. 
673 
Section II. C h l a m. y d o s p o n je. Reproduction chiejly hj ova contained in 
defined ova-cells or ovaria,'' strengthened with siliceous spicules^ some- 
times at length becoming solid spheres formed of siliceous spicules radiating 
from a central point. 
Order VI. SPH^ROSPONGIA. Characters those of the subsection. 
Family 16. GEODiADic. Sponge massive, fleshy ; pores with a constrictive 
valve. Ovisacs siihglohose or oblong, with a thick coat formed of spicules 
in lines radiating from the axis to the circumference, and at length be- 
coming solid, congregated on the outer surface, or scattered in the flesh. 
Spicules elongate ; the larger ones with two or three expanded or re- 
curved branches on the outer ends ] smaller ones simple, often extending 
beyond the surface. 
Genera : — Pachgmatisma, Bowerb. : P. Johnstonia (Bk.), Gray, 1. c. p. 647. 
Geodia, Lamk. ; G. gibherosa (Lamk.), Gray, 1. c. p. 648. Cgdonium, Flem. : 
C. barretti (Bk.), Gray, 1. c. p. 648. Erylus, Gray : E. mammilaris (Sdt.), 
Gray, 1. c. p. 649. D’iate, Gray ; T. discop>hora (Sdt.), Gray, 1. c. p. 649. 
Caminus, Sdt. ; C. vulcani (Sdt.), Gray, 1. c. p. 649. 
Family 17. PLACOspONGiADiE. Sponge branched, coral-like, with a central 
axis and a hard outer coat entirely formed of solidified ova. The axis 
and outer lamina separated from each other by a layer of sarcode 
strengthened with bundles of spicules. 
Genus : — Placospongia, Gray : P. mclobesioides, Gray, 1. c. p. 649. 
Order VII. POTAMOSPONGIA. Ovisacs coriaceous, scattered in the tissue 
of the sponge, especially near the base. The cells coriaceous, with 
a permanent central cavity, strengthened externally with superficial 
spicules. 
Family 18. Spongilladje. Sponge massive or branched. Skeleton formed 
of a network of spicula, more or less united together by homy matter j 
network symmetrical, four-sided. 
Genera : — Ephydatia, Gray : E.fiuviatilis (Bk.), Gray, 1. c. p. 660. Eosilia, 
Gray : D. plumosa (Carter), Gray, 7. c. p. 651. Metania^ Gray : ilf. gregaria 
(Bk.), Gray, 1. c. p. 651. Acalle, Gray : A. recurvata (Bk.), Gray, L c. p. 662. 
Druliuj Gray: i). brownii (Bk.), Gray, 1. c. p. 632. Eunapius, Gray: E. car- 
teri (Bk.), Gray, 1. c. p. 662. Spongilla, Gray : S. lacustris (Flem.), Gray, 1. c. 
p. ^62. Eiplodemia, Bowerb. : B. vesicula (Bk.), Gray, 1. c. p. 663. 
Subclass n. PO RIPER A CALC AREA. 
Skeleton composed of calcareous spietdes, tvhich are generally three-rayedy 
stellate. 
Family 19. GuANxiAPiE. Sponge tubular or massive, pierced with a tubular 
cloaca. Outer surface hispid, covered with three-rayed spicules. 
Genera: — Grantia, Flem. : G. ciliata, Flem., Gray, 1. c. p. 664. Ute, Sdt. : 
U. capillosay Sdt., Gray, 1. c. p. 664. Artynes, Gray : A. compressa (Johnston), 
Gray, 1. c. p. 666. Leucosolcnia, Bk. : L. botryoidcs, Bk., Gray, 1. c. p. 666. 
Leuconia, Grant : L. nivea (Flem.), Gray, 1. c. p. 666. Leucogypsia^ Bk. : 
L. gosseij Bk., Gray, l.c. p. 667. Clathrina, Gray: C. sulphurea, Gray=: 
Grantia clathrus (Sdt.), Gray, 1. c. p. 667. Lelapia, Gray : L. australis^ Gray, 
Z.c. p.657. 
Family 20. ALCYONCELLiDiE. Sponge tubular, simple or branched. Outer 
surface tessellated, formed of square perforated cells. Oscules terminal. 
